Stokes偏振仪波片快轴方位误差敏感性研究

摘要

针对波片快轴方位误差严重影响旋转波片Stokes偏振仪的入射光Stokes矢量的反演精度等问题，本文提出一种研究波片快轴方位误差敏感度及误差最小化的方法。首先，推导出由波片方位误差向SV反演误差的传递矩阵W，利用协方差矩阵研究Stokes矢量反演误差向量，提炼出评价偏振仪误差敏感度的参数EWV。其次，研究了EWV与波片方位角、波片位相延迟量和光强测量次数的关系。最后，为了抑制三种主要误差源对Stokes矢量反演的影响，对4次光强测量的旋转波片Stokes偏振仪中波片方位与波片位相延迟量进行了研究。结果表明，基于参数EWV的波片快轴方位误差敏感度及误差最小化的方法可以有效描述波片快轴方位误差对Stokes矢量的反演精度的影响，提高Stokes矢量反演精度。%To delve into the bad influence on the precision of reconstructing incident Stokes vector (SV) caused by the azimuth error of the retarder,a method was proposed to minimize the sensitivity and azimuth error of the retarder. Firstly,in order to understand the effect of the azimuth of the retarder on SV reconstruction,the error transferring ma-trix W from the azimuth error of retarder to SV reconstruction error was derived,and SV reconstruction error was ana-lyzed by means of covariance matrix to abstract the figure of merit EWV charactering the error sensitivity of the po-larmeter. Secondly, the relationships between EWV and the azimuth of the retarder, between EWV and the retardance of the retarder, between EWV and intensity measurement number were investigated. Finally, it was concluded that the errors from the three major error sources for the polarimeter doing 4 measurements might be effectively restrained. The results indicate that the influence of the wave plate fast axis azimuth error on the Stokes vector retrieval accuracy can be described effectively based on the minimization method of EWV parameters azimuth error sensitivity, thus improving SV reconstructive accuracy.